Yarn treating apparatus



y 1963 R. P. BECHER 3,097,412

YARN TREATING APPARATUS Filed Aug. 8, 1961 INVENTOR ROBERT PAUL BECHERATTORNEY United States Patent 3,097,412 YARN TREATEN G APPARATUS RobertPaul Becher, Wilmington, Del., assignor to I. du Pont de Nemours andCompany, Wilmington, Del, a corporation of Delaware Filed Aug. 5, 1951,Ser. No. 130,110 4 Claims. ((11. 28-1) This invention relates to anapparatus to be used in treating a bundle of filaments such as a yarn toproduce a bulky strand composed of a plurality of individuallyconvoluted filaments.

Artificial fibers are normally produced most easily as continuousfilaments. Their extreme uniformity and lack of discontinuity makesconventional textile filament yarns much more dense than yarns made fromstaple fibers. The production of yarns from staple fibers, however, istime consuming and requires a complex series of operations. The occludedair spaces in staple fiber yarns gives them a lightness, covering powerand warmth-giving bulk not normally possible with continuous filamentyarns.

The bulk, covering power and recoverable elongation of continuousfilament yarns have been greatly improved by a variety of mechanicaland/or heat setting processes. The most recently developed product inthis area is described in US. Patent No. 2,783,609 to Breen. This lattertechnique involves exposing a filamentary material to a rapidly movingturbulent fluid thereby introducing a multitude of crunodal filamentloops at random intervals along the individual filaments. These loopsand snarls of entangled loops, together with the other convolutions increase the bulk of the continuous filament yarns considerably and resultin fabrics of improved cover, bulk, handle, and the like. The essence ofthis new bulking tool of Breen is a turbulent fluid. A new apparatus orjet has now been discovered for utilizing the turbulent fluid techniqueof Breens to produce improved yarn products with highly usefulproperties.

The object of this invention is to provide a jet which will uniformlycombine multiple ends of yarn to a uniform bulky product. A particularlyinteresting variation of this process is the so-called core-texturingtechnique. In core texturing, one or more ends are fed to a jet at arelatively slow feed rate and to become the core of the yarn formed whenother ends of effect yarn are overfed simultaneously to the same jet ata much greater rate of speed, i.e., 2-4 times the rate of the core yarn.The types of jets of this invention are also particularly useful in theblending and/or cotexturing of glass fiber yarns to get improveduniformity and stability of bulk.

FIG. 1 illustrates the jet used in practicing the invention.

FIG. 2 is an embodiment showing means for feeding core and effect yarnsat ditferent rates to a texturing jet.

The apparatus of which FIGURE 1 is a specific embodiment is made up ofthree basic components: a hollow cylindrical body 7; an orifice block 6;and a hollow yarn needle 5. The jet assembly combines the body whichholds the component parts in the desired spatial relationship andprovides a plenum chamber for air or other compressed fluid which isadmitted through a suitable opening 8. The orifice block 6 has a taperedorifice throat 1 and an exit conduit 3 which may be cylindrical ortapered. The hollow needle 5 has a tapered needle tip 2 through whichthe yarn enters the bulking chamber. The orifice throat I and the needletip 2 must be conical sections of substantially the same included angle.The combination of the orifice throat and the needle tip provides aconical annular nozzle which directs a stream of compressed air or othersuitable fluid to the center of the conduit 3.

The yarn needle 5 discharges the yarn preferably concentrically into thebulking zone 4 where it is immediately penetrated by the fluid streamsthat impinge upon the yarn. The zone of turbulence so created exerts anopening action on the yarn components, so that the filaments are formedinto loops and whorls by the action of the fluid.

The geometry of the air chamber 4 formed by the position of the needletip 2 in relation to the orifice throat I is generally important forproper operation of the jet. The taper of these two conical sections maybe varied from 45l35. The actual angle may be important for specificfibers, but generally speaking, any taper within these two extremes ishighly useful.

Contrary to the teaching of the prior art, e.g., British Patent No.793,044, of April 9, 1958, and US. Patent No. 2,884,756, of May 5, 1959,the two mating conical sections must have substantially the sameincluded angle. This angle may be varied between wide limits asdescribed in the preceding paragraph, but the conical sections mustmatch almost precisely. The reason why this is neces sary is notunderstood. However, intimate blending of the two or more componentyarns cannot be achieved unless this condition is met. The velocity ofthe texturing fluid as it passes through the annulus surrounding theneedle approaches sonic velocity and precise control of the conicalsections is needed to accurately meter the air and control theturbulence.

The other important parameter of the jets of this invention is therelative length of the two mating conical sections, i.e., needle tip 2vs. orifice throat 1. The specific embodiment shown in FIGURE 1 is thesame as that used in the examples wherein the length ratio of needle tip2 to throat 1 is 1:4. Obviously a wide range of ratios with either andabove infinity will operate to texture yarns to a greater or lesserdegree. For the specific embodiment of this invention, which is directedto core-texturing and cotexturing and aimed in part, at least, towardsthe special processing characteristics of fiber glass, this ratio mustbe within the limit of 1:2 to 1:6.

The jet can be made to be adjustable or non-adjustable. As shown inFIGURE 1 it is non-adjustable and would be the type used for multipleinstallments for production runs to process a few very closely relatedmaterials needing essentially equivalent conditions for optimumproduction. A more versatile variation can be made by threading the capportion 9 of needle 5 where it fits around the body portion 7. Therotation of the needle 5 will vary the spatial relationship of throat Iand needle tip 2, changing the amount and velocity of fluid impinging onthe yarn. Such an apparatus vasiation will allow the processing of agreat variety of yarns through the same jet, since yarns of dissimilarcharacteristics frequently need different texturing conditions foroptimum operability. Since there is only a single simple adjustment tobe made in operating the apparatus, uniformity of processing from onemachine or one plant location to another and from one operator toanother can be maintained within very close limits permitting theproduction of uniform yam products with a very minimum of control andwithout the need for highly skilled operators.

In operation, air is forced into annular chamber 10 within body 7 by wayof lateral conduit 8. Then the air passes through the tapered annulusbetween throat I and needle tip 2 to the turbulent zone 4 adjacent tothe needle tip. The zone of turbulence 4 is created between the flat endof the needle 5 and inner end of the outlet conduit 3 as the fluidrushes into this area from all sec tions of the annulus. Yarn is fedinto the zone of turbulence 4 through yarn passageway 11 in needle 5,where it is agitated violently and whipped about and exits throughconduit 3 along with the high velocity air. The yarn is removed from theair stream immediately upon issuing from conduit 3 by withdrawing it toone side. It

is important that the apparatus have dimensions such that the air orother suitable compressible fluid utilized will have a velocity equal toat least /2 sonic velocity and preferably approaches sonic velocitywhere it first strikes the yarn in the zone of turbulence 4, and thatthe crosssectional area of the outlet conduit 3 be of sufiicient size tomaintain backpressure in the yarn inlet at a minimum withoutsubstantially decreasing yarn velocity in the zone of turbulence.

The absolute and relative dimensions of the yarn inlet tube 5 and theoutlet conduit 3 may be varied fairly widely but conduit 3 must be thelarger one. One advantage of this apparatus is the effectiveness inprocessing a great variety of yarn counts without necessity of a changein the dimensions. For example, with a yarn inlet passageway 11 having adiameter of 0.028 inch, yarns varying in denier from about 80 to 1100 ormore may be readily processed using an outlet conduit diameter of 0.056inch. An inlet passageway diameter of 0.040 inch with an outlet conduitdiameter of 0.070 inch is suitable for processing yarns varying indenier from about 500 to 2300 and is especially good for processingglass fiber yarns or mixing two or more synthetic organic filamentyarns. The specific dimensions of the orifice tlnoat or the yarn inletmay be varied widely. An optimum dimension depends upon the yarn beingprocessed and. the degree of texturing desired. Typical diameters forthe outlet conduit run from 0.056 inch and lower to 0.070 inch andhigher. The yarn inlet diameters are preferably considerably smaller andcan be varied from below 0.020

up to 0.052 and higher. A particularly useful combination :for texturedglass fiber yarns is one wherein the yarn inlet diameter is 0.040, Whilethe outlet conduit diameter is 0.070. Both dimensions, of course, can bincreased considerably if .it is desired to texture very heavy denieryarns of the order of 23005,000 denier or higher.

For maximum operability, the cross-sectional area of the outlet conduit3 should be at lea-st 50% greater than the cross-sectional area of theyarn inlet passageway 11 just prior to the entry into the bulkingchamber 4. The ratio of these two cross-sectional areas can be variedbetween 1:l.5 up to 1:6.

While this jet has been described as being particularly useful forcotexturing multiple ends of glass fiber yarns, it can also be used totexture and bulk any natural or synthetic filamentary material. Singleends of multiple filament yarns can be bulked in a given jet, but thisparticular apparatus is peculiarly suitable for bulking multiple ends:of yarn. Suitable synthetic filamentary yarns include polyamides, e.g.,poly(epsilon caproamide), poly (hexamethylene adipamide); celluloseesters; polyesters, e.g., polyethylene terephthalate,poly(hexahydro-p-xylylene terephthalate), etc.; polyvinyls andpolyacrylics, e.g., polyethylene and polyacrylonitrile, as well ascopolymers thereof, are particularly suitable for producing theuniformly bulked products described herein. While the preferred form ofmaterial is continuous filaments, the process and resultant improvementsoccur with staple yarns as well. Both types of materials can be madeinto bulky yarns and fabrics having improved bulk, covering power(opacity) and hand.

This apparatus and process are useful for both multifilament yarns intextile deniers as well as the heavier carpet and industrial yarn sizeseither singly or combined in the form of a heavy tow. Fine count andheavy count staple yarns can be processed both as singles and plied.Cruoi form, Y-shaped, delta-shaped, ribbon, and dumbbell and other suchfilamentary cross sections can be processed at least as well as roundfilaments and usually contribute still more bulk than is obtained withround filaments. By proper design of the jet and process, multiple endsof yarn may be handled either in the form of warp sheets, ribbons, ortows.

The over-feed rate of the yarns will depend upon the character of thefeed yarn as well as the particular characteristics desired in theproduct. When the apparatus is used to combine and bulk two or moreyarns, one or both may be overfed to the jet and the overfeed of theyarns may be the same or different. Overfeeds as high as 1200% or higherhave been used effectively.

Air is particularly preferred as a treating fluid because of itscheapness and convenience. However, steam or any other suitablecompressible fluid or vapor may be utilized.

The efficient bulking action of this apparatus apparently results fromthe action of high velocity iiuid on the individual yarn filaments asthe yarn passes through the zone of turbulence at the tip of the yarninlet needle. It appears that the yarn is opened up due to the action ofthe fluid in the zone of turbulence and that the individual filamentswithin the yarn bundle are separately whipped about and randomly twistedso that they become intimately entangled and interlocked with adjacentfilaments while at the same time being formed into loops and whorlsuniformly through the yarn bundle to provide the desired bulking action.Apparently also, a fluid vortex is formed so that in addition to theloopy characteristics in the yarn product and the individual twist,intermingling and interlocking of fibers within the yarn bundle, theyarn bundle itself assumes an alternate twist configuration whichremains in the yarn after it is removed from the apparatus.

Quite possibly it is the interlocking and intermingling of the yarnfibers within the bundle which make this apparatus particularly suitablefor bulking fiber glass yarns because processing such a fiber glass yarnproduces a compact yarn bundle which is coherent and further processablein the same manner as a unitary strand. Prior art fluid treatingapparatuses for bulking yarns have been less eflfeetive for thetexturing of multiple ends and especially for core-texturing of fiberglass yarns since the resulting product was usually neither coherent norunitary. Because of the unifying results produced by the apparatus ofthis invention, the feed yarn may twisted or untwisted and the productmay be twisted or not, as desired. Where a zero twist yarn is fed to theapparatus, the product is a bulked yarn in which the filaments areintermingled and interlocked with one another besides being uniformlyloopy throughout and there is no need to twist this product for furtherprocessing.

The following example utilizes the apparatus of FIG- URE 2 and the jetof FIGURE 1. This jet provides superior blending of fibers and colors ascompared to prior art jets. The yarns are much more symmetrical togetherwith better anchoring of effect yarn to core and at higher productivityrates. The relative conditions and fed yarns are as indicated in thetable.

EXAMPLE A simple embodiment which shows means for feeding core andeffect yarns at dilTerent rates to the texturing jet is shown in FIGURE2. Yarn 12 to be treated according to this invention may be suppliedfrom package 16 through pigtail guides 13 and 14, to pass about cork cot15 rotating in contact with drive roll 17 and into the nip of thisfeed-roll arrangement. The yarn then enters jet or nozzle 18; from thejet outlet the yarn is drawn through pigtail 19 about drive roll 21 andinto the nip of it with cot 20, about which the yarn passes on its wayto the twister. The yarn goes through center guide 23 and throughtraveler 24 moving about ring 25 mounted on rail 26, then onto bobbin27, rotated on spindle 28 by belt 29. Core yarn 30, which is suppliedfrom package 32 through pigtail guide 33, also passes through guide 19,the forwarding rolls, center guide, the traveler, and onto bobbin 27,along with the yarn treated by the jet. Typical operating conditions forproducing different types of yarns are set forth in the table.

Table Feed yarn Feed rate y.p.n1. Air Wind p, Ex. Jet 1 pre s., y.p.m.Product p.s.1.g. Core Eliect Core Effect 1. 2 ends 66-nylon, 70/34/1/2Z2 ends cellulose acetate, 300/80/0. 105 230 1 75 100 Moderate sizechenille type yarn.

2 1 end 66-nyl0n, 140/68/l/2Z 2 ends cellulose acetate, 3013/80/25. 16225 1 75 Very heavy chenille.

1 end (SB-nylon, 70/34/1/2Z 1 @5713 golzyethyleneterphthalate, 60 190 255 57 Finely looped boucle yarn.

4 Bends glass fiber, 150-1/01Z 1 end glass fiber, 1501/0-1Z 43. 5 90 360 40 Uniform novelty boucle yarn.

1 See the following table:

Jets Conical section length Cross-sectional area ratio rationeedle/orifice needle/orifice threat Since many different embodiments ofthe invention may be made without departing from the spirit and scopethereof, it is to be understood that the invention is not diameter thanthe exit conduit aligned with the axis of the exit conduit, the needlehaving a cap portion closing the end of the body opposite the orificeblock to form a chamber surrounding the needle, the needle having a tipin the form of an conical section the apex angle of and to provide anannular passageway around the needle tip from the chamber to thetreating zone, and an inlet conduit for introducing air into saidchamber from outside the body.

2. The yarn treating apparatus defined in claim 1 wherein said yarnpassageway has a diameter of about 0.04 inch and said exit conduit has adiameter of about 0 0.07 inch.

3. The yarn treating apparatus defined in claim 1 wherein said conicalorifice throat has a length of about 4 times the length of the conicalsection forming the needle tip.

4. The yarn treating apparatus defined in claim 1 wherein said exitconduit has a cross-sectional area which is from 1.5 to 6 times thecross-sectional area of said yarn passageway.

which is from 45 to 135, said conical orifice throat References Clted mthe file of this patent having a precisely matching angle and a lengthfrom 2 UNITED STATES PATENTS to 6 times the length of the correspondingconical section 2,884,756 Head May 5, 1959 of the needle, the conicalneedle tip being completely 2,982,000 Gonsalves May 2, 1961 spaced fromthe orifice throat to provide a yarn treating 2,982,082 Pool May 2, 1961zone between the tip of the needle and the exit conduit 2,994,938Loveland et a1. Aug. 8, 1961

1. YARN TREATING APPARATUS COMPRISING A HOLLOW CYLINDRICAL BODY, ANORIFICE BLOCK CLOSEING ONE END OF THE BODY INCLUDING A CONICAL ORIFICETHROAT AND A CYLINDRICAL EXIT CONDUIT WITH THE AXES ALONG THECYLINDRICAL AXIS OF THE BODY, A YARN NEEDLE POSITIONED IN AND CONCENTRICWITH THE BODY HAVING A LONGITUDINAL YARN PASSAGEWAY OF SMALLER DIAMETERTHAN THE EXIT CONDUIT ALIGNED WITH THE AXIS OF THE EXIT CONDUIT, THENEEDLE HAVING A CAP PORTION CLOSING THE END OF THE BODY OPPOSITE THEORIFICE BLOCK TO FORM A CHAMBER SURROUNDING THE NEEDLE, THE NEEDLEHAVING A TIP IN THE FORM OF AN CONICAL SECTION THE APEX ANGLE OF WHICHIS FROM 45* TO 135*, SAID CONICAL ORIFICE THROAT HAVING A PRECISELYMATCHING ANGLE AND A LENGTH FROM 2 TO 6 TIMES THE LENGTH OF THECORRESPONDING CONICAL SECTION OF THE NEEDLE, THE CONICAL NEEDLE TIPBEING COMPLETELY SPACED FROM THE ORIFICE THROAT TO PROVIDE A YARNTREATING ZONE BETWEEN THE TIP OF THE NEEDLE AND THE EXIT CONDUIT AND TOPROVIDE AN ANNULAR PASSAGEWAY AROUND THE NEEDLE TIP FROM THE CHAMBER TOTHE TREATING ZONE, AND AN INLET CONDUIT FOR INTRODUCING AIR INTO SAIDCHAMBER FROM OUTSIDE THE BODY.